Hey all, I've been playing SMN as my main since launch and I thought I would share some insight to do with global cooldown (GCD) and how to use it to maximise your damage output.
What is GCD? The time it takes in between casting another spell, typically it is 2.5 seconds however can be reduced by spellspeed/skillspeed.
Spells which can be used during GCD (Off GCD) include: Rouse, Spur, Swiftcast, Fester, Bane, Aetherflow, Virus, Eye for an Eye, Enkindle
If you are not utilising off GCD spells during the GCD you are therefore losing perfectly good opportunities to be casting essential spells in your rotation. For example, if you cast Bio you have to wait until the cooldown has finished to cast Shadowflare. Yet if you use Swiftcast first (As you should be doing with Shadowflare anyways because it has the longest cast time not counting Resurrection) which is an off GCD ability you can use it straight away and then Shadowflare. This minimises the amount of downtime you have picking your nose which can be better spent casting something you were going to cast later anyway. Another example is using Ruin II which has a GCD and then Fester (Off GCD) straight afterwards.
Ruin II: Wildly misunderstood and one of the most important spells for SMN out there, don't let anyone tell you otherwise.
Pros: Instant Cast- this makes it not only useful when moving in fights such as Titan X but that it gives you a GCD allowing for you to efficiently use spells like Rouse right afterwards rather than a Ruin I which takes 2.5 seconds to cast and then Rouse. You're looking more at around 1.5 seconds in comparison to 3 seconds depending on latency.
Cons: If used incorrectly it can REALLY exhaust your mana pool. It is almost impossible for a SMN to run out of mana if only using Ruin I, but if you just spam Ruin II it will deplete it entirely and then you'll be in the unfortunate situation of having to use Energy Drain instead of something more effective like Fester.
So do the pros outweigh the cons? Absolutely. Basically Ruin II should be used before all abilities off GCD because it's instant dps and can be followed up by another ability you should be using anyway. You just have to be mindful of your mana, not casting it by accident at the wrong time, and when Aetherflow is coming off cooldown. Long story short: Yes, it is possible to always use Ruin II prior to an off GCD ability and not run out of mana if you have good awareness
Thanks for letting me know how to get around the 1000 character lock ♥